Light source arrangements of the generic type are used as light-emitting means for projector lamps which need to provide a high luminous efficacy for a wide variety of lighting purposes. Projector lamps of the generic type are, for example, vehicle headlamps, lighting devices for data and video projection and for digital cinema film projection, effect projector lamps in the entertainment industry and lighting devices for technical, industrial and medical applications. The luminous efficacies desired for such purposes generally require very voluminous light sources. The conventional light sources of the generic type furthermore may have the disadvantage that they require a high degree of maintenance and are restricted in respect of reliability. Furthermore, their efficiency is limited. These requirements have made light sources based on semiconductors appear to be unsuitable until now. Light sources based on semiconductors are, for example, light-emitting diodes or else semiconductor laser diodes. However, such light sources are very restricted in respect of the luminous efficacy, so that, at best, very voluminous arrangements with a very large number of corresponding semiconductor light sources need to be provided, which furthermore require a complex, voluminous and expensive deflection unit in order to be able to focus the multiplicity of light beams generated by the light sources in a suitable manner in order that the desired lighting effect can be achieved.
Furthermore, use of conventional semiconductor laser light sources requires particular measures, in particular also in respect of the fact that semiconductor laser diodes are available at present only with an optical power of a few watts. At desired total optical powers of 100 W or more, therefore, a corresponding number of semiconductor laser diodes need to be connected to one another and to be operated jointly, wherein the laser light beams generated thereby need to be combined via a suitable deflection unit. Owing to the comparatively large number of individual semiconductor laser light sources, a physical size which is determined critically by the number and arrangement of the semiconductor laser light sources and the deflection unit results for the conventional light source arrangement. If a high luminous efficacy is desired, the system integration has proven to be very complex.
Such a conventional light source arrangement is disclosed in U.S. Pat. No. 6,356,577. In this case, a plurality of semiconductor laser light sources arranged in rows in a single row are arranged in connection with a deflection unit in such a way that the laser light beams provided by the semiconductor laser light source arrangements formed in this way are deflected onto a common beam plane. For this purpose, a deflection unit is provided, which is formed from a number of mirror elements connected to one another in the direction of the row and which deflects the laser light beams provided by the semiconductor laser light source arrangements laterally offset with respect to one another onto the common beam plane. The result of U.S. Pat. No. 6,356,577 is that the semiconductor laser light source arrangements arranged in rows can be arranged spaced apart from one another, so that mutual influencing, in particular as regards thermal loading, can be reduced. At the same time, this teaching does entail the disadvantage, however, that the light source arrangement based thereon requires a very voluminous design with the further disadvantages associated therewith as regards beam quality and cost. The use of such deflection units as are required for the abovementioned teaching has proven to be complex in terms of design and furthermore requires a very large amount of installation space. Furthermore, comparatively long beam paths are required in the deflection unit, which counteract a reduction in the physical size. Finally, the arrangement of the semiconductor laser light source arrangements in the form of rows with respect to the deflection unit requires increased mechanical complexity in order to be able to achieve the required accuracy for the beam guidance or deflection of the laser light beams. For the manufacture of modern, compact projector lamps and projection units, in particular for mobile use, for example in the case of vehicles or in the case of video projection, this design is unsuitable.